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<li class="toctree-l4"><a class="reference internal" href="threaded_1.html"><code class="docutils literal notranslate"><span class="pre">threaded/1</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="threaded_call_1_2.html"><code class="docutils literal notranslate"><span class="pre">threaded_call/1-2</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="threaded_once_1_2.html"><code class="docutils literal notranslate"><span class="pre">threaded_once/1-2</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="threaded_ignore_1.html"><code class="docutils literal notranslate"><span class="pre">threaded_ignore/1</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="threaded_exit_1_2.html"><code class="docutils literal notranslate"><span class="pre">threaded_exit/1-2</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="threaded_peek_1_2.html"><code class="docutils literal notranslate"><span class="pre">threaded_peek/1-2</span></code></a></li>
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  <p class="align-right"><strong>built-in predicate</strong></p>
<section id="threaded-cancel-1">
<span id="predicates-threaded-cancel-1"></span><span id="index-0"></span><h1><code class="docutils literal notranslate"><span class="pre">threaded_cancel/1</span></code><a class="headerlink" href="#threaded-cancel-1" title="Link to this heading"></a></h1>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="k">threaded_cancel</span>(<span class="nv">Tag</span>)
</pre></div>
</div>
<p>Cancels a tagged threaded call. When there is no asynchronous call with the
given tag, calling this predicate succeeds assuming the asynchronous call
has already terminated or canceled. The threaded call identifier tag is
generated by calls to the <a class="reference internal" href="threaded_call_1_2.html#predicates-threaded-call-1-2"><span class="std std-ref">threaded_call/2</span></a>
and <a class="reference internal" href="threaded_once_1_2.html#predicates-threaded-once-1-2"><span class="std std-ref">threaded_once/2</span></a> predicates. Tags
shall be regarded as an opaque term; users shall not rely on their type.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This predicate requires a <a class="reference internal" href="../../glossary.html#term-backend-Prolog-compiler"><span class="xref std std-term">backend Prolog compiler</span></a> providing
compatible multi-threading primitives. The value of the read-only
<a class="reference internal" href="../../userman/programming.html#flag-threads"><span class="std std-ref">threads</span></a> flag is set to <code class="docutils literal notranslate"><span class="pre">supported</span></code> when that
is the case.</p>
</div>
</section>
<section id="modes-and-number-of-proofs">
<h2>Modes and number of proofs<a class="headerlink" href="#modes-and-number-of-proofs" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="k">threaded_cancel</span>(<span class="o">+</span>nonvar) <span class="o">-</span> one
</pre></div>
</div>
</section>
<section id="errors">
<h2>Errors<a class="headerlink" href="#errors" title="Link to this heading"></a></h2>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">Tag</span></code> is a variable:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">instantiation_error</span></code></div>
</div>
</div>
</section>
<section id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
<p>(none)</p>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="threaded_call_1_2.html#predicates-threaded-call-1-2"><span class="std std-ref">threaded_call/1-2</span></a>,
<a class="reference internal" href="threaded_exit_1_2.html#predicates-threaded-exit-1-2"><span class="std std-ref">threaded_exit/1-2</span></a>,
<a class="reference internal" href="threaded_ignore_1.html#predicates-threaded-ignore-1"><span class="std std-ref">threaded_ignore/1</span></a>,
<a class="reference internal" href="threaded_once_1_2.html#predicates-threaded-once-1-2"><span class="std std-ref">threaded_once/1-2</span></a>,
<a class="reference internal" href="threaded_1.html#predicates-threaded-1"><span class="std std-ref">threaded/1</span></a></p>
</div>
</section>
</section>


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